Alterations of factor VIII von Willebrand factor in clinical conditions associated with an increase in its plasma concentration.
Factor VIII-related antigen (VIIIR:Ag) was consistently higher than factor-VIII procoagulant activity (VIII:C) in 57 patients with clinical conditions characterized by acute-phase reactions. Two different methods for measuring VIII:C (one- and two-stage assays) and VIIIR:Ag (electroimmunodiffusion and immunoradiometric assay) gave concordant results in the majority of cases. In 43% of plasma samples, crossed immunoelectrophoresis in agarose gel was characterized by the appearance of an additional, fast-moving precipitin peak which was immunologically identical with the major, slower-moving VIIIR:Ag peak. The fast-moving peak was detected in all the patients with clinical conditions typically associated with increased plasma proteolysis (DIC, acute pancreatitis, during thrombolytic therapy). It was present in a smaller proportion of cases with liver and renal failure and malignancies and in the post-operative period. The additional VIIIR:Ag peak is thought to be the result of in vivo factor VIII/von Willebrand factor fragmentation by proteolytic enzymes.
D000941:Antigens / Q000378:metabolism; D001779:Blood Coagulation Factors / Q000032:analysis*; D005169:Factor VIII / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional; D007676:Kidney Failure, Chronic / Q000097:blood; D008103:Liver Cirrhosis / Q000097:blood; D009369:Neoplasms / Q000097:blood; D010195:Pancreatitis / Q000097:blood; D013924:Thrombophlebitis / Q000097:blood; D014841:von Willebrand Factor / Q000032:analysis*
D000941:Antigens; D001779:Blood Coagulation Factors; D014841:von Willebrand Factor; D005169:Factor VIII